When it comes to LS swaps, one of the most critical components you’ll need to get right is the fuel delivery system. Without a reliable fuel pump, even the most carefully built engine won’t perform as it should. The right fuel pump ensures your LS engine gets the proper volume and pressure of fuel, whether you’re running a stock setup or pushing serious horsepower. Let’s break down what you need to know to make the best choice for your build.
First, consider your engine’s power goals. A basic LS swap with a stock or mildly modified engine might only require a factory-style fuel pump. However, if you’re aiming for higher horsepower—say, 400+ horsepower—you’ll need a pump that can handle increased demand. Forced induction builds, like turbo or supercharged setups, will demand even more from your fuel system. In these cases, a high-flow pump isn’t just an upgrade; it’s a necessity.
One popular option among LS enthusiasts is the Fuel Pump from Kemso Racing. This pump is designed to handle high-performance applications, delivering consistent fuel pressure and volume even under heavy load. It’s compatible with both return-style and returnless fuel systems, making it a versatile choice for a wide range of LS swap projects. What sets it apart is its durability—constructed with quality materials, it’s built to last through years of demanding use.
Another factor to consider is whether you need an in-tank or external fuel pump. In-tank pumps are generally quieter and cooler-running since they’re submerged in fuel, which helps prevent vapor lock. External pumps are easier to access for maintenance but may require additional plumbing and noise-dampening measures. For most LS swaps, an in-tank setup is the way to go, especially if you’re using a modern fuel tank designed for electric pumps.
Don’t overlook the importance of proper voltage and wiring. A weak electrical connection can starve your fuel pump, leading to lean conditions and potential engine damage. Upgrading to a relay kit or a dedicated power circuit ensures your pump gets the voltage it needs. This is especially crucial if you’re running a high-performance pump that draws more current than a stock unit.
Installation tips can make or break your fuel system’s reliability. Always use ethanol-compatible hoses and fittings if you plan to run ethanol-blended fuels, which are common in performance applications. Double-check clamps and seals for leaks, and consider adding a fuel pressure gauge to monitor your system’s health. A sudden drop in pressure could indicate a failing pump or a clogged filter—both issues you’ll want to catch early.
Budget is another consideration, but remember: cutting corners on a fuel pump can lead to costly repairs down the line. While there are affordable options that perform well, prioritize brands with proven track records in the LS community. Reviews and forums are great resources to see how specific pumps hold up in real-world conditions.
Finally, think about future upgrades. If you’re starting with a mild build but plan to add more power later, invest in a pump that can grow with your engine. Many high-flow pumps are adjustable or can be paired with boost-referenced regulators, giving you flexibility as your project evolves.
In summary, the best fuel pump for your LS swap depends on your horsepower goals, fuel system type, and long-term plans. Prioritize quality, compatibility, and durability—and don’t forget to support your pump with proper wiring and maintenance. With the right setup, you’ll keep your LS engine running smoothly, whether you’re cruising the streets or hitting the track.